N.Y. CPL Law § 280.10

§ 280.10 Motion for mistrial.\n At any time during the trial, the court must declare a mistrial and\norder a new trial of the indictment under the following circumstances:\n 1. Upon motion of the defendant, when there occurs during the trial\nan error or legal defect in the proceedings, or conduct inside or\noutside the courtroom, which is prejudicial to the defendant and\ndeprives him of a fair trial. When such an error, defect or conduct\noccurs during a joint trial of two or more defendants and a mistrial\nmotion is made by one or more but not by all, the court must declare a\nmistrial only as to the defendant or defendants making or joining in the\nmotion, and the trial of the other defendant or defendants must proceed;\n 2. Upon motion of the people, when there occurs during the trial,\neither inside or outside the courtroom, gross misconduct by the\ndefendant or some person acting on his behalf, or by a juror, resulting\nin substantial and irreparable prejudice to the people's case. When\nsuch misconduct occurs during a joint trial of two or more defendants,\nand when the court is satisfied that it did not result in substantial\nprejudice to the people's case as against a particular defendant and\nthat such defendant was in no way responsible for the misconduct, it may\nnot declare a mistrial with respect to such defendant but must proceed\nwith the trial as to him;\n 3. Upon motion of either party or upon the court's own motion, when\nit is physically impossible to proceed with the trial in conformity with\nlaw.\n